This changes `ShareForumActivity` to use two fragments to facilitate
forum sharing with the new Forum Sharing Client backend.
The `ContactSelectorFragment` allows the user to select a
number of contacts. If there is an ongoing sharing session or the forum
is already shared with the contact, it is disabled in the list. If there
is at least one contact selected, a button appears in the toolbar that
brings the user to the `ShareForumMessageFragment` where the user can
write an optional message to be send along with the invitation.
After sending an invitation, the user is brought back to the forum that
she shared and there is a snackbar showing up briefly to indicate the
successful invitation.
The invitation is shown along with the message within the private
conversation of each contact. The person who shares the forum also sees
the invitation and the message as outgoing messages that also display
the current status of the messages.
A notification is shown like for other private messages as well.
Please note that this commit does not include a way for users to respond
to invitations.
This commit replaces the old ForumSharingManagerImpl with a new one
which is based on state machines and the ProtocolEngine.
There is a SharerEngine and a InviteeEngine that take care of state
transitions, messages, events and trigger actions to be carried out by
the ForumSharingManagerImpl. This is all very similar to the
Introduction Client.
The general sharing paradigm has been changed from sharing as a state to
sharing as an action. Now the UI can allow users to invite contacts to
forums. The contacts can accept or decline the invitiation. Also, the
Forum Sharing Manger is notified when users leave a forum.
Closes#322
* If the user has already declined, we don't show that the other
introducee has declined as well. The backend doesn't have that information, so
this is compatible with the principle of showing what we know.
* If the user has already accepted or hasn't yet responded, we show the
decline response in the private conversation with the introducer. If
the user hasn't yet responded, we hide the accept/decline buttons
in the introduction request message.
Messages an introducee receives in a `FINISHED` state are now being
ignored and deleted.
Closes#295
Remove the Toast that always says 'Message Sent' and show graphical
indicators instead that show either:
* message is waiting to be sent
* message was sent (or requested)
* message was delivered
